Palustriella Ochyra, 1989.

Palustriella are easy to confuse with Cratoneuron filicinum. The paraphilia of Cratoneuron are lanceolate; those of Palustriella are linear and more numerous. In the field Brachythecium frigidum can be mistaken for Palustriella, but the former species has some of the leaves near the stem apices with laterally twisted apices.

A. Stem leaves deltoid-triangular with a somewhat cordate base, abruptly narrowed near the leaf middle into a long acumen; alar cells forming a large group in the cordate base .....Palustriella commutataA. Stem leaves lanceolate and falcate, gradually narrowed from near the base to the long acuminate apex; alar cells forming a small group to 5 cells long at margin .....Palustriella falcata not known from CA